Prehensility is the quality of an organ that has adapted for grasping or holding. Examples of prehensile body parts include the tails of New World monkeys and opossums, the trunks of elephants, the tongues of giraffes, the lips of horses and the proboscides of tapir. The hands of primates are all prehensile to varying degrees, and many species (even a few humans) have prehensile feet as well. The claws of cats are also prehensile. Many extant lizards have prehensile tails (geckos, chameleons, and a species of skink). The fossil record shows prehensile tails in lizards (Simiosauria) going back many million years to the Triassic period - Celeskey (2005).

Prehensile tails in animals such as monkeys are articulated and thus limited to some degree in flexibility. Zippel (1994) discovered that Corucia zebrata - underlined, the Solomon Islands monkey skink has a prehensile tail that has a snow cone muscle structure that is loosely attached to the vertebrate but has a sronger connection to an outer shealth. This makes the tail omnidirectional and give the monkey skink the means to move one part of its tail in one direction while the other remains rigid or moves in a different direction. This is often orchestrated in an angry male establishing territorial dominance.

Proboscises are evolutionary adaptations that have allowed species to have a great natural advantage for manipulating their environment for feeding, digging, and defense. It enables many specialized animals such as primates to use tools in order to complete tasks that would otherwise be impossible. For example, chimpanzees have the ability to use sticks to fish for termites and grubs.

The word is derived from the Latin term prehendere, meaning "to grasp."